The organisers of one of Britain's best-known gay pride marches have been accused of profiteering after insisting that all those who take part must pay £50 for the privilege.

Next month's 10-day Manchester Pride festival, now in its 12th year, is expected to attract 100,000 people to the city centre. But for the first time, organisers are insisting that the costs of crowd control and additional policing, which have grown with the event, demand that individuals or non-commercial groups on the event's march through the city must pay.

The decision has angered many in the lesbian and gay community. Gordon Pleasant, one of the organisers of Manchester's first Mardi Gras parades in the early 1990s, said he was particularly appalled at the idea of those with HIV and Aids being asked to pay. "I always believed that you could not put a price on certain things, like human dignity and pride," he said.

"Charge the commercial companies who want to take part in the parade and advertise themselves, by all means - but not the individuals who want to walk in the parade." Manchester Pride, which organises the three-day weekend festival and has raised more than £400,000 for charities in Greater Manchester over the past three years, insisted the flat charge of £50 plus VAT was justifiable. "I would love to throw the biggest and best event in the world, but you are acutely aware that every pound you are spending is a pound less going to charities," said the event's chairman, Andrew Stokes. "These things always have a cost attached and there are all sorts of health and safety costs. And, while it is not directly attributed to this, we don't currently have a parade sponsor. "

Businesses will be made to pay far more to join the march - a total of £1,250, for which they can be seen to demonstrate their commitment to equal opportunities for lesbian and gay employees and customers.

But the £50 charge, which comes on top of the £15 entry fee to the gated site on Canal Street, where the main three-day festival known as the Big Weekend takes place, is out of keeping with the "village", according to many who have attended from the start.

"Those early years were great, it was a real charity event with everyone having a great sense of community," one festival regular said. "Now it's too big and commercial. The biggest amount of money made is by the businesses and not the charities, which is after all what it's all about. It should be about gay pride and not about money."

Canal Street's struggle to retain the essence of its lesbian and gay culture is a familiar one. The popularity of hen parties, an indirect result of the street's promotion by the TV drama Queer as Folk, was seen to be damaging the atmosphere for which it was once known. Four years ago the event, then known as Mardi Gras, was temporarily abandoned amid claims that the police were being homophobic by limiting an alcohol tolerance zone in the city centre to Canal Street rather than a wider area. A compromise was reached.

To mark the enactment of the Civil Partnership Act, this year's Manchester Pride will include an event at which lesbian and gay couples are invited exchange vows at Manchester Register Office on 24 August.